Electrical apparatus for therapeutic and other purposes



April 21, 1931 E. J. Rosa 1,801,385

ELECTRICAL APPARATUS FOR THERAPEUTIC AND OTRE R PURPOSES Filed Oct. 14,1929 4 Sheets-Sheet 1 91 3 I; I H0 INVENTOR.

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ATTO EYS.

E. J. Ross April 21, 1931 ELECTRICAL A PPARATUS FOR THERAPEUTIC ANDOTHER PURBOSES- Filed Oct; 14. 1929 4 Sheets-Sheet 2 W =HW aIIIIII'IIIIIIII' IIIIIII'III )IIIII'IIIIIIIIIIIIII .77 Dunn,

Y'JNVENTOR. [aye 11%;:

ATTORNEYS.

April 21, 1931. E. J. ROSE 1,301,385

ELECTRICAL APPARATUS FOR THERAPEUTIC AND OTHER PURPOSES Filed 001;. 14,1929 4 Sheets-Sheet 3 ,I y 31 I 32 g? i 35 34 i so 29 1 u 20 s X LLI 23; 12 ,6 34 b 1' INVENTOR.

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April 21, 1931. J ROSE 1,801,385

ELECTRICAL APPARATUS FOR THERAPEUTIC AND OTHER PURPOSES Filed Oct. 14,1929 4 Sheets-Sheet 4 Pom Ciumcen Swift 3 DouN-E POL: nouuzfunon Rfll TOPATIENTS Swncu INVENTOR. f 090/1 Rose,

ATTORNEYS power currents or Patented Apr. 21, 1931 UNITED STATES PATENTOFFICE EDGAR J. ROSE, OF L08 LNGELES, CALIFORNIA Application filedOctober 14, 1929. Serial No. 399,463.

This invention relates to improvements in electrical apparatus of thetype in which mechanism is provided to modify a basic electrical currentsuch as direct or alternating alvanic or faradic battery currents or oter currents created by various mechanical and chemical means, and tocreate in a circuit delivered from this ap aratus sur es and slow wavesof variable vo tages and orms which may be used preferabl as therapeuticagents, and may be time to correspond with the actions of the muscles,respiratory action of the human body or other animals. Basic or primarycurrents employed may be from selected sources or power currents orsupplied by special generator or rectifier or battery of cells formingpart of the apparatus or machine. These asic currents which arecommercially known as direct currents, are referred to in medicalpractice as galvanic currents. Alternating currents are generallyreferred to in medical practice as rapid sinusoidal or rapid pulsatorycurrents. The basic currents may be made to surge in various shapedwaves or their directions reversed at predetermined intervals by themechanism herein described, and the various waves produced will havedifferent characteristics. They may also be controlled by the apparatusas to voltage and amperage, and the direct or pulsatory currents may bemodified or unmodified in form.

The apparatus is primarily designed for the production of currents to beused for therapeutic or medical purposes but it will also be understoodthat the modified currents produced thereby may be employed for otherpurposes, such as industrial, scientific or other commercial purposeswithin the scope of the invention as set forth.

An important object of this invention is to'provide for production ofelectrical current waves which may be made to correspond to the normalor abnormal actions of muscle and generally to produce electricalcurrent waves of various forms or characteristics which are necessary ordesirable for therapeutic and medical, as well as other scientificpurposes.

Another object of the invention is to provide for production ormodification of various forms of current waves without the use of cams,cones, or intermittent Geneva stop mechanism which have heretofore beenused for that purpose and have been open to the objection of causingincessant trouble and requiring continual service for maintaining themin operative condition.

Another important object of the invention is to provide for eliminationof oscillations when using the apparatus for production of rectifiedalternating electric currents. Other objects of the invention willappear hereinafter.

The accompanying drawings illustrate embodiments of my invention andreferring thereto:

Fig. 1 is a front elevation of the apparatus.

Fig. 2 is a plan view of the apparatus with the cover broken away toshow the various electrical devices mounted on the base thereof.

Fig. 3 is a rear elevation of the apparatus shown in Fig. 2.

Fig. 4 is a side elevation of the apparatus shown in Fig. 2, viewed fromthe left.

Fig. 5 is a rear elevation of the variable speed mechanism.

Fig. 6 is a side elevation of the switching means for changing fromalternating to rectified current operation.

Figs. 6 and 6" are detail elevations of cam means for operating suchswitching means.

Fig. 7 is a section on line 77 in Fig. 6.

Fig.8 is a section on line 8-8 in Fig. 4.

Fig. 9 is a diagram of the circuit connections.

Fig. 10 is a series of diagrams of different wave forms which can beproduced by the operation of the apparatus.

The apparatus is preferably mounted in a casing comprising a base 1 anda cover mounted on said base, a part of the electrical apparatus beingmounted on the base and some of the electrical devices being preferablymounted on the cover as shown. I have shown as mounted on the base atransformer 4 for furnishing alternating current to the apparatus from asuitable supply line, rectifying means 5, electric swltchmg means 6 forchanging from alternating to rectified current and vice versa, automaticcurrent modifying means 7 and an electric motor 8 for operating saidautomatic current modifying means. The forward portion of the covermeans, indicated at 2, is preferably secured in fixed position on thebase 1 and various instrumentalities for control of the operation of theapparatus are preferably mounted thereon, the rear portion 3 of thecover member being removably mounted for access to the apparatus.

The switch means 6 may comprise a vertical plate 9 of insulatingmaterial mounted on the base 1, for example by bars 10 extending from aframe 11 secured to said base, and four rows or series of switch devicesmounted on saidinsulating plate for changing the circuit connections soas to provide for production of either alternating or rectified current.One set of switch devices comprises movable members, indicated at 12,13, 14 and 15 (see Fig. 6) which are respectively pivoted to theinsulating plate 9, for example, one above another, in a vertical rowand are connected by an insulating link or bar 16 so as to move inunison. Each of these movable switch members cooperates with fixedcontacts as hereinafter described.

A lever 19 mounted to rock on a pivot 19 on a suitable support 20carries at the outer end of one arm thereof a fork 22 which embraces apin 23 on the bar 16 so that rocking movement of the lever 19 will movethe bar 16 and cause operation of the switch members 12, et cetera, inone direction or the other. Such operation of the rocking lever 19 iseffected by cam means (see Figs. 2, 6 and 7) engagmg a pin or roller 24on one arm of lever 19, said cam means 25 being carried by a shaft 26mounted in fixed hearings on frame 11. Shaft 26 is operated manually inany suitable manner, for example by means of a gear wheel 28 on saidshaft 26 engaged by a gear wheel 29 on a shaft 30 which is mounted inbearings on frame 11. Said gear wheel 29 is also engaged bya pinion 31on a shaft 32 which is mounted in hearings on frame 11 and extendsthrough the front of the casing of the apparatus, being provided withmanual operating means, such as a thumb nut or handle 33' (Figs. 1 and2).

The cam means 25 may consist of a disc as shown provided with twonotches 34 and 35 (see Fig. 6") and with inclined projections orshoulders 34, 34 and 35 35", at either side of the respective notches,adapted to engage the said pin 24 in the rotation of the said disc inone direction or the other so as to force the pin through one or theother of said notches in the disc and turn the lever 19 so as to raiseor lower the switch members in connection therewith.

Fixed contacts are provided on insulating plate 9 for cooperation withthe movable switch members 12, 13, etc., said contacts being numbered 36to 42 inclusive.

Another set of switch members 44, 45 and 46 mounted on insulating plate9 is adapted to cooperate with fixed contacts 47 to 52 inclusive on saidinsulating plate, said switch members 44, 45 and 46 connected to operatein unison by means of insulating bar 54 carrying a.

pin 55 which is engaged by a fork 56 on a lever 57 pivoted at 58 to asuitable support on the frame 11. A pin or roller 60 on one arm of saidlever 57 is engaged by a cam means 61 so as to operate the severalswitches 44, 45 and 46, the cam means 25 and 61 both mounted on theoperating shaft 26 but being arranged in different angular positionsthereon so as to operate the respective sets of switches at differentangular positions of the shaft. Cain means .61 may consist of adischaving a notch 62 (see Fig. 6) with inclined projections 62 and 62" atopposite sides thereof and adapted to engage the pin or roller 60 .toturn the. lever 51 one way or the other according to the direction ofrotation of shaft 26.

I An indicating wheel or drum 64 (see Figs. 2, 3 and 4) is mounted toturn on a shaft 65 on the frame 11 and is operated by suitable means soas to rotate in correspondence with I the rotation of the operatingshaft 32, for example, by means of a sprocket chain 66 engaging withsprocket wheels 67 and 68 respectively onthe shaft of said indicatingwheel and on a shaft 7 0 mounted in hearings on the frame 11 andconnected by gearing 71 and 72 with the shaft 26 aforesaid. Said drum 64is provided with indicating marks 63 corresponding to the differentforms of current to be produced and received through a right opening 81in the casing means 2.

Means are provided for modifying the current under control of the samehandle 33 which operates the switching means aforesaid. For this purposethe shaft 32 may be provided with a crank wheel 69 to which is pivotedat 73 a link member 74 having a pivotal connection 7 5 with the frame 74of an electric motor 8 mounted to slide on guides 77 carried by the base1 so that thesaid electric motor may be shifted longitudinally in eitherdirection throughout a definite stroke on said guideways by operation ofthe handle 33 on sha ft32. A rotary member 78 is mounted to turn inbearing 7 8 on the frame and is connected by suitable speed reducinggearing to the shaft of the motor 8 so as to be rotated by said motor,said gearing being enclosed within the casing at 80 and forming a partof the motor equipment. Said rotary member is provided with a channelmember 82extending diametrically with reference to the 'axis of rotationof said member 78 and on each side of such axis A shaft 84 mounted infixed bearings 85 on the base 1 is provided with an arm 86 carrying apin or roller 87 adapted to engage in the channel means 82 on the rotarymember 78 so as to cause rotation of shaft 84 by rotation of the saidrotary member, said means 82 and 87 constituting coupling meansconnecting members 78 and 84 in such manner as to effect variable speedrotation of the member 84 by constant speed rotation of member 78. Asprocket wheel 88 on shaft 84 is connected by a sprocket chain 89 to asprocket wheel 90 on a shaft 91 mounted to turn in a frame 92 on thebase 1 and forming a part of the current modifying mechanism 7hereinafter described.

On the frame 92 of the current modifying mechanism is mounted by meansof bars 94 an insulatin plate 95 on which is wound a resistance winding96, this winding consisting of suitably insulated wire, such as enameledwire preferably of high resistant metal and of very small diameter so asto provide the necessary resistance in a single layer wound on theinsulating plate 94 aforesaid. The insulation of such resistance wire isremoved on the side toward the rotary contact means hereinafterdescribed so as to provide for electrical contact between the resistancewire and movable contact members or brushes 98 and 99 of said rotarycontact means which travel over said resistance winding.

The rotary contact or commutator means indicated at 100 consists of adisc carrying the brushes 98 and 99 which are insulated from said discby means of bushings 101 and are connected respectively (as shown inFig. 8) to two collector rings 102 and 103 mounted on and insulated fromthe disc 100. A split contact ring comprising two semicircular sections104 and 105 is also mounted on and insulated from the disc 100, section104 being connected to brush 99 (as shown in Fig. 8) and section 105being without circuit connection. Brushes or contacts 106, 107 and 108are mounted on and insulated from the frame 92, brushes 106 and 107being adapted to cooperate respectively with the contact rings 102 and103 and brush 108 belng adapted to contact with the split contact ringsections 104 and 105.

Means may also be rovided for visually indicating that the evice isfunctioning properly, said means comprising for example a cam 110mounted on the shaft 91 of rotary member 100 and adapted to engagecontact s rings 112 and 113 which cooperate with xed contacts 114 and115 to close circuits leading to indicating lamps 116 and 117 mounted onthe front of the casing. The respective contact springs 112 and 113 maybe provided with insulation indicated at 118 at the points where theyare engaged by cam 110 aforesaid.

Various other instrumentalities mounted on the casing for the apparatus,will be refcrred to in connection with the electrical circuitconnections, which are shown in Fig. 9. The apparatus is adapted forencrgization from an alternating current service circuit (for example110 volt) indicated at 120, connectcd through a main switch 119 to theprimary winding of transformer 4. This transformer may have twosecondary windings 121 and 122. winding 121 being adapted to produce say110 volts in a main operating circuit and winding 122 being adapted toproduce a low votage in an indicating circuit hereinafter described.

The main operating circuit leads from winding 121 by wire 124 to motor8. From motor 8 a connection 1226 leads to the other side of winding121. this connection including a variable resistance 128 for regulatingf the motor speed, the operating handle for controlling this resistancebeing mounted on the front of the casing as indicated at 128' in Fig. 1.A connection 127 leads from wire 124 through a resistance to contact 51for switch 46. and from said switch means a wire 129 leads to switch 14,contact 41 for said switch being connected by wire 130 to one end of theresistance element 96 of the current modifying means. From the other endof resistance element 96 wire 131 leads contact 36 of switch 12 and alsoby wire 131 to switch 45, the contact 49 thereof being connected by wire132 to wire 126 aforesaid. and being also connected by wire 133 toswitch member 44. It will be noted that contacts 47 and 43 4 shown inFig. 6 are idle or unconnected contacts and are omitted from Fig. 9.Contacts 40 and 38 are connected as shown in Fig. 9.

A potentiometer 134 is provided, compris- 1' ing resistance or impedancemeans connected at its ends by wires 135 and 136 respectively to switchmembers 12 and 13. The operating handle for the potentiometer is mountedon the casing as indicated at 134' in Fig. 1. I.'

From the contact- 37 for switch member 12, a wire 138 leads to a switch140 whose operating handle is indicated at 140' in Fig. 1. Switch 140 isprovided with contacts 141 and 142, contact 141 being connected by wire14; I

preferably of duplicate construction so as to i provide forrectification of both halves of the alternating current wave. The wires147 and 148 are connected to the alternating cui= rent input terminalsof the rectifier, and the wires 150, 151 are connected to the rectifiedcurrent output terminals thereof. One side of transformer coil 121 isconnected to one input wire 147 of the rectifier, the other input wire148 being connected to contact 48 for switch 44, said switch havingconnection by wires 133, 132 and 126 with the other side of thetransformer winding 121. One output wire 150 of the rectifier isconnected to contact 50 for switch 45. The other output wire 151 of therectifier is connected through a choke coil 154, wire 152, a double poleswitch 155 and 156 and wire 153 to contact 52 for switch 46. Capacitiesor condensers 158 and 159 may be provided in branches across therectifier connections for assisting the action of the choke coil inproducin a smooth rectified current. A wire 157 leads from wire 151 to acontact 160 for switch arm 156.

The potentiometer 1.34 serves to supply current of any desired voltageto the applicator circuit, one side 161 of such circuit being connectedto one end of the potentiometer winding and the other side 162 of saidcircuit being connected to the movable contact of the potentiometer. Thetwo circuits 161 and 162 may be connected through a pole changing switch163 and milliammeter174 to the terminals 164 and 165 for makingconnection to the patient. In Fig. 1, the handle for the pole-changingswitch is indicated at 163' and applicators 166 and 167 are shown asconnected to the terminals 164 and 165.

The pilot lights 116 and 117 on the casing are connected through wires168 and 169 to switches 112 and 113 connected by wire 170 to one side ofthe low voltage 112 of the transformer 4, the other side of each of saidpilot lights being connected by wire 171 to switch 15, contact 42 ofsaid switch being connected by wire 172 to the other side of winding112. The operation is as follows: The primary position of the apparatusis assumed to be that of supplying unmodified alternating current to thepatient. In that case the switch means 44, 45 and 46 are in the positionshown in Fig.9, but switch means 12. 13, 14 and'15 are in raisedposition so that switches 12, 13 and 14 connect with contacts 36, 38 and40 respectively, and switch 15 is out of contact. The current passesfrom the secondary winding 121 of the transformer 4 through wire 124,resistance 125, wire 127, contact 51, switch 46, wire 129, switch 14,contacts 40 and 38, switch 13 and wire 136 to one side 'of thepotentiometer resistance 134. From the other side of the potentiometerthe connection is continued through wire 135, switch 12, contact 36,wire 131', switch 45, contact 49 and wires 132 and 126 to the other sideof transformer winding 121.

' ing to the voltage of the winding 121 as modified by the resistance125. The function of the transformer 4 in this case is to applysubstantially full line voltage to the apparatus while, removing theapparatus from any ground or main line connection. By means of thepotentiometer handle, thepoint of contact with the potentiometer may bevaried so as to apply any desired voltage of the applicator circuit 161and 162 so that in the stated case there is applied to the patient analternating current (such as represented graphically at a in Fig. 10) ofthe desired voltage and without any modification by the currentmodifying means 7, the circuit traced being independent of said currentmodifying means. This corres onds to one extreme position of the controling handle 33 and is indicated on the drum 64 by suitable marking, (suchas Rapid sinusoidal) which is exposed through the sight opening 81 atthis time.

In case a modified current is desired the handle 33 is turned and theshaft 32 thereby operated, and said shaft through the gearing 31, 29 and28 operates the shaft 26 so as to rotate the cams25 and 61 thereon. Atthis time the connecting link 74 is at one extreme end of its stroke,the crank wheel 69 being on substantially dead center position so thaton the initial movement of the shaft 30 no substantial shiftingof themotor 8 is produced. The position of motor 8 at this time is such thatthe channel member 82 engages with the means 87 at a point of contactwhich travels back and forth between the center of rotation of thechannel member and one end of said channel member so as to produce anextreme modifying effect as hereinafter, described.

The initial movement of the shaft 30 causes pin or member 24 on lever 19to pass through the slot 34 in the cam means 25 by the operation of theinclined projection 34 and the inclined face of the slot, so that member24-passes to the other side of the cam disc 25, and in this operationlever 19 is shifted so as to move the bar 16 and the switches 12, 13,etc., to position shown in Fig. 9. This places the apparatus undercontrol of the current modlfying means, the circuit being traced asfollows: from the transformer winding 121 through wire 124 and theconnection as traced above to switch 14, thence through contact 41 andwire 130 to resistance winding 96 of the current modifying means andfrom said winding through wires 131 and 131' to switch 45 and fromcontact 49 by wires 132 and 126 to the other side of the trans formerwinding.

The motor 8 is in operation at this time through connection includingwire 124, resistance 128 and wire 126, this connection indeed beingestablishedwhen the main switch 119 is closed irrespective of theoperation of the switches 12, 13, etc., but the operation of the motorbeing without effect when the switches 12, 13, etc., are in initial orraised position as above described. When, however, the switches 12, 13,etc., have been moved to osition shown in Fig. 9, the current modif yingmeans is connected in the circuit and causes a continual modification orvariation of the current by reason of the travel of the brushes 98 and99 over the resistance wire 96, it being understood that (with theresistance wires extending vertically as shown in Fig. 8) when thebrushes are in horizontal position substantially the full voltageapplied to the resistance 96 will be taken up by the brushes 98 and 99and communicated through collector rings 106 and 107 to thepotentiometer circuit connections but when the brushes 98 and 99 are invertical position they will contact with portions of wire 96 which areat zero potential diflerence so that the eflect of rotation of themember 100 is to cause a gradual variation and periodic reversal of thevoltage applied to the potentiometer.

If the member 100 is rotated at a uniform rate, the variation of voltageproduced thereby Will follow a uniform approximately sinusoidal curve.In the stated position of the parts, however, where the pin 87 is nearone outer end of the transverse channel 82 in rotating member 7 8, theeffect of uniform rotation of member 78 is to produce a non-uniformrotation of member 86 connected to the modifier disc 100, and thearrangement is assumed to be such'thatthe most rapid motion of member100 is when it is taking maximum voltage from resistance 95 therebygiving the effect of a sharp peak in the voltage applied to thepotentiometer as indicated at 2 in Fig. 10 and the indicator drum '64 isprovided with suitable marking to indicate this type of current waveillustrated at b in Fig. 10.

The connection from the brush 98 of the current modifying means isthrough collector ring 102, brush 106, wire 143, switch 140, wire 138,contact 37, switch 12 and wire 135 to the potentiometer and from theother side of the potentiometer by wire 136, switch 13, contact 39, andwire 145 to brush 107. The mechanical connection by means 88, 89, 90,between rotary member 86 and commutator means 100 is such that theformer makes two revolutions for each revolution of the latter, so thatthe current modifying mechanism effects a complete cycle of speedvariation during the period of one-half of a revolution of the rotarycontact means. In the'stated position of the control means, the movementof the contact means is rapid during each uarter rotation in which thevoltage taken from the resistance means 95 is near a maximum, eitherpositive or negative, and is slow during each quarter rotation when thevoltage being taken from the resistance means is near the minimum,therebyproducing the peak effectas stated.

In the rotation of the members 78 and 86, the pin or roller 87 is atcertain times in contact with the channel member 82 at a point at ornear the center of rotation thereof, and at this time the arm 86 isnearly or quite at rest whereas at other times the pin or roller 87 isin engagement with the channel member 82 near an outer end thereof sothat at such times the arm 86 is subject to rapid motion.

By operation of the handle 33, the motor 8 and the rotary member 78connected thereto may be shifted transversely with relation to the axisof rotation of member 86 so as to decrease the inequality of motion ofthe arm 86 in the uniform rotation of the member 78, and by this meansthe peak effect may be reduced as indicated at 0 in Fig. 10.

By a further motion of the operatin handle 33, the axis of rotation ofthe mem r 78 may be brought into alignment with the axis of rotation ofmember 86 and the two members 78 and 86 will then rotate in unison anduniformly, producing a sine variation of the sinusoidal alternatingcurrent as indicated at d in Fig. 10.

By further operation of the handle 33 the asymmetric action of thechannel member 82 with referenceto the pin or roller 87 may be shiftedto the other side of the center of ro tation so that the commutatormember 100 will move slower at the times when it is taking maximumvoltage from the resistance coil 96, and will move more rapidly when thebrushes thereon are at minimum potential difference. The effect of thisis to produce a dwell or sustained peak effect as indicated at e, thegraph f indicating a more prolonged dwell effect and corresponding tothe extreme position of the channel members 82 with reference to the pinor roller 87. 6

By operation of the mechanism constituted by members 78, 82, 86 and 57,therefore, the commutator of the current modifying means may bealternately accelerated and retarded so as to produce any desiredmodification of the current.

In the above described operation, the crank wheel 69 has been moved onehalf turn in the operation of the handle member 33, producing a completestroke of the motor carriage in one direction and during this operationthe switches have been maintained in position for supplying alternatingcurrent to the applicator circuit as above described, subject tomodification by the current modifying means.

Further operation of the operating handle 33 will cause cam 25 tocooperate with roller 24 so as to cause cam 61 to cooperate with the pinor roller 60 so as to force the said pin or roller through the slot 62in said cam and turn lever 57 which operates bar 54 through pin 55 so asto move the switches 44, 45 and 46 to lowered position in which theycontact respectively with contacts 48, 50 and 52."

The circuit connection may then'be traced fromone side of windin 121direct to input wire 147 of the rectifier, and from the other side ofWinding 121 throughwire 126,

132 and 133, switch 49 and contact 48 to the a K constructionandarrangement of the appaotherinput wire 148 to the rectifier.Rectified current from the rectifier passes through output wire 150, tocontact 50, switch 45, wire 131 and 131 to one side of resistance 96,and from the other. side of said resistance by wire 130, contact 41,switch 14, wire 129, switch 46, contact 52, wire 153, switch means 155,156 (whose uppercontacts are connected by wire 156), wire 152 and chokecoil 154 to the other output wire 151 of the rectifier. v V

The effect of these connections is to apply to the potentiometer 134 arectified current which is subject to almodification by the currentmodifying means 7 above described. At the initiation of this furthermovement of the operating handle 33, the crank wheel is just starting onits return movement so that the members 78 and87 are still at relativeposition corresponding to a sustained peak effect producing current suchas indicated bythe graph 9 in Fig. 10 which may be designated on theindicator drum as sustained galvanic or other suitable designation.

In the further movement of the operating handle 33, the asymmetricoperation of the rotary means 78 and 87 is reduced as shown at k in Fig10, and when the axes of rotation are again brought into alignment, asine variation such as indicated at z in Fig. 10 is produced. Furtherrotation of the handle 33 produces a peak effect of progressiveintensity as indicatedat j and I:. At the end of this return stroke ofthe motor shifting means, pin 24, passes through slot 35 to the otherside of the cam means 25, thus restoring the parts to original position.

By operation of the switch means 155, 156 so as to open connection at155 and close contact at 156, 160, the choke coil 154 may be cut out,the current passing from contact 160 directly by wire 157 to output wire151 of the rectifier, with the result that pulsating efl'ect such asindicated in graphs 9 and y" may be produced, it being understood thatsimilar pulsations may be produced in connection with any of therectified impulses. By shifting switch 140 to contact at 142, thecircuit connection may be diverted through wire 144 to brush 108 so asto take off only a half wave at each alternation of the currentmodifying means, the corresponding graphbeing indicated at g" for one ofthe rectified wave forms and such half wave impulses may also beproduced with pulsations, by cutting out the choke coil. 7

The apparatus described above therefore provides for application to thepatientof various forms or modalities of current either alternating orrectified and with various modulations in accordance with the setting ofthe controlling handle, the character of the currentbeing applied at anytime being indicated on the indicator drum. 1

Various modifications may be made in the ratus without departing from myinvention, provided that the general principle of operation remains thesame. For example, in the mechanism for imparting a variable speed tothe current modifying commutator the rotary channel member may bemounted either on the driving member asshown or, by reversal of theconstruction, the channel member may be mounted on the driven rotarymember, suitable modificaitons being made in the operating andindicating means.

Furthermore, while I have described a particular form of currentmodifying means, it will be understood that I may use any suitable meansfor establishing moving contact with a resistance means so as to takeoff a current of continually varying voltage from a supply circuit.

I claim: I

1. In apparatusof the character described, the combination of resistancemeans, means for applying a definite voltage to said resistance means,contact means mounted to travel over said resistance means to collectcurrent of. varying voltage therefrom, a motor and a variable speedmechanism comprising a rotary driving member operated by said motor, arotary driven member and variable speed coupling means connecting saidrotary driving member and said rotary driven member to operate saidrotary driven member at variable speed by constant speed operation ofsaid rotary driving member, in such manner that the speed Variation ofthe rotary driven member passes through a complete cycle during eachrotation of said rotary driven member and means connecting said rotarydriven member to said contact means to operate said contact meansthrough a complete cycle of variation during each half rotation of saidrotary driven member, so as to effect alternative rapid and slowmovement of the contact means in successive 'quarter revolutions of saiddriven member and thereby cause modification of the current delivered bysaid contact means. v a.

2. In apparatus of the characterdescribed, current modifying meanscomprising a modifying resistance winding having an exposed portion, arotary commutator having contact means adapted to travelv over saidexposed portion of the winding and provided with means for deliveringcurrent from said contactmeans, means for supplying current to forrotation by said motor at uniform speed, a rotary driven memberconnected to said rotary contact member to operate the same and meansconnecting said rotary drivin member and said rotary driven member ancomprising a channel means on one of said members and a projection ofthe other of said members adapted to engage said channel means to effectrotation of the driven member by rotation of the driving member andmeans for shifting the said motor and driving member transversely to theaxis of rotation of said rot: ry driving member to vary the engagementbetween therotary driving member and the rotary driven member so as tomodify the s ed of the driven member in different portions of rotationthereof.

3. Apparatus of the character described, comprising a current modifyingresistance means, circuit connections for supplying current to saidresistance means, a rotary commutator having two contact means adaptedto travel over said resistance means for taking current of variablevoltage therefrom, applicator circuit connections adapted to receivecurrent from said travelling contact means, an electric motor, operatingcircuit connections for said motor, a rotary driving member connectedfor operation by said motor, a driven member, said driving and drivenmembers being provided with means for interengagement and for varyingthe point of engagement with reference to the centers of rotation ofsaid members, and manual controlling means and mechanism operatedthereby to shift the electric motor in either direction throughout adefinite stroke so as to vary the point of engagement of the rotarydriving and driven members, and thereby accelerate o'r retard the motionof the commutator to vary the current delivered thereby.

4. An apparatus as set forth in claim 3 and comprising in addition,means in connection with the connections for supplying current to themodifying resistance means, for supplying alternating or direct currentalternatively to said resistance means.

5. An apparatus as set forth in claim 3 and comprising in addition,means in connection with the connections for supplying current to themodifying resistance means, for supplying alternating or direct currentalternatively to said resistance means, and switch means connected foroperation by said manual controlling means, for changing the connectionsfrom alternating current to direct currentconnections or vice versa.

6. Apparatus of the character described, comprising alternating currentsupply connections, a current modifying resistance, a rectifier, switchmeans for connecting said modifying resistance means to the alternatingcurrent supply connections directly or through said rectifier, a rotarycommutator cooperating with said resistance means to take therefromcurrent of a voltage continually varying and reversing with the rotationof said commutator, current delivery circuit connections for deliveringcurrent from said commutator, an electric motor connected for operationfrom said supply connections, manually operated means for shift- 7Apparatus as set forth in claim 6 and comprising in addition, meansincluding a switch and also including contact means, in connect-ion withsaid commutator for taking ofi' current in one direction only therefrom.

8. Apparatus as set forth in claim 6 and comprising in addition, a chokecoil in the circuit connections of said rectifying means and switchmeans for placing said choke coil in or out of operative connection.

, 9. In apparatus of the character described, current modifying meanscomprising a modifying resistance winding having an exposed portion, arotary commutator having contact means adapted to travel over saidexposed portion of the winding and provided with means for deliveringcurrent from said contact means, means for supplying current to saidresistance winding, applicator circuit connections for receiving currentfrom said current delivering means, and means for operation of saidrotary commutator comprising a motor, a rotary member connected forrotation by said motor at uniform speed, a rotary driven memberconnected to said rotary contact member to operate the same, a couplingmeans on one of said members extending diametrically thereof and meanson the other of said members adapted to engage said coupling means toeffect rotation of the driven member by rotation of the driving memberand means forshifting the said motor and driving member transversely tothe axis of rotation of said rotary driving member to vary theengagement between the coupling means and the means for engaging thesame so as to modify the speed of the driven member in differentportions of rotation thereof.

10. Apparatus of the character described, comprising a current modifyingresistance means, circuit connections for supplying current to saidresistance means, contact means adapted to travel over said resistancemeans for taking current of variable voltage therefrom, rotary operatingmeans for said contact means, applicator circuit connections adapted toreceive current from said traveling contact means, an electric motor,operating circuit connections for said motor, a rotary driving memberconnected for operation by said motor, a rotary driven member connectedto operate the rotary operating means for the same contact means, saiddriving and driven members being provided with means for interengagementand for varying 10 the point of engagement with reference to the centersof rotation of said members, and manual controlling means and mechanismoperated thereby to shift said driving member in either directionthroughout a definite 'stroke so as to vary the point of engagement ofthe rotary driving and driven members, and thereby accelerate or retardthe motion of the commutator to vary the current delivered thereby.

In testimony whereof I have hereunto subscribed my name this 3d day ofOctober, 1929.

EDGAR J. ROSE.

